Jigmey Kunsang pauses in back of his counter at the gym where he makes protein shakes for customers Wednesday February 5, 2014 in San Francisco, Calif. Jigmey Kunsang works at a minimum wage job and finds it hard to make enough money at a cafe inside the Fitness SF off Brannan Street. less

Jigmey Kunsang pauses in back of his counter at the gym where he makes protein shakes for customers Wednesday February 5, 2014 in San Francisco, Calif. Jigmey Kunsang works at a minimum wage job and finds it ... more

Photo: Brant Ward, The Chronicle

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SAN FRANCISCO, CA - FEBRUARY 20: Gap employee Shinju Nozawa-Auclair folds clothes at a Gap store on February 20, 2014 in San Francisco, California. Gap Inc. announced that they will raise their minimum wage for U.S. employees to nine dollars in June of 2014 and to $10 by June of 2015. (Photo by Justin Sullivan/Getty Images) less

SAN FRANCISCO, CA - FEBRUARY 20: Gap employee Shinju Nozawa-Auclair folds clothes at a Gap store on February 20, 2014 in San Francisco, California. Gap Inc. announced that they will raise their minimum wage ... more

Photo: Justin Sullivan, Getty Images

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California Gov. Jerry Brown signs a bill to raise California minimum wage in Los Angeles Wednesday, Sept. 25, 2013. Brown has put his signature on a bill that will hike California's minimum wage to $10 an hour within three years. The legislation signed Wednesday will raise the current minimum of $8 an hour to $9 on July 1, 2014, and then to $10 on Jan. 1, 2016. (AP Photo/Nick Ut) less

California Gov. Jerry Brown signs a bill to raise California minimum wage in Los Angeles Wednesday, Sept. 25, 2013. Brown has put his signature on a bill that will hike California's minimum wage to $10 an hour ... more

Ron Unz, right, discusses economic issues with Ken Jacobs, Chair with the Center for Labor Research and Education for the Institute for Research on Labor and Employment, before the two participated in a live televised discussion about minimum wage with host Thuy Vu December 6, 2013 at the KQED building in San Francisco, Calif. less

Ron Unz, right, discusses economic issues with Ken Jacobs, Chair with the Center for Labor Research and Education for the Institute for Research on Labor and Employment, before the two participated in a live ... more

Raising San Francisco's minimum wage to a nation-topping $15 an hour has broad support in a new poll obtained by The Chronicle - a strong sign that voters will have a chance to weigh in on the city's widening wealth disparity gap in November.

One reason, according to the poll, is because skyrocketing housing costs are reshaping the city's face: 45 percent of respondents in the new survey say friends or family have moved out of the city in the past two years because they could no longer afford to live there. Nearly a third said they were likely to leave in the next five years. Sixty-one percent of the LGBT respondents said family or friends have been priced out over the past two years.

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The survey of 400 likely November voters found that 59 percent of respondents support raising the minimum wage from its current $10.74, which is adjusted with the regional rate of inflation. San Francisco already has the highest big-city starting wage in the country. SeaTac, a small city near Seattle's airport, recently approved a $15 an hour floor.

The new poll found that 36 percent of the respondents opposed a jump to $15, and 5 percent were undecided. The survey, which was funded by several unions that support raising the minium wage, has a margin of error of 4.9 percentage points.

Advocates and pollsters were thrilled - and somewhat stunned - at the level of support, especially considering that San Francisco's electorate in off-year elections is older (62 percent are over 50 years old) and whiter (63 percent) than in presidential years, which analysts say makes it comparatively conservative, at least by San Francisco standards.

Plus, the low level of undecided voters indicates that most people have made up their minds about the issue.

Big change in 11 years

The national attitude toward the minimum wage was different 11 years ago, when San Francisco voters last approved raising the minimum wage.

President Obama now talks about raising the federal level from $7.25 an hour. Gov. Jerry Brown signed legislation last fall to raise California's minimum wage, currently at $8 an hour, to $10 by 2016. Even former California GOP gubernatorial candidate Ron Unz wants to boost the state level - he is currently gathering signatures to up it to $12 in 2016.

In the Bay Area, the public has become more attuned to wealth inequality over the past two years as San Francisco has become the national case study on the haves and have-nots. According to a recent study by the Brookings Institution, the gap between San Francisco's wealthy residents and its poor ones is growing faster than in any other city in the nation.

"We have never seen numbers this high" on concerns over the cost of living and the "availability of housing for people like you," said Shanan Alper, a pollster with David Binder Research, a San Francisco-based firm that has done polling for Obama.

Alper had little doubt that a $15-an-hour measure would pass in November, though it falls just short of the magic number of 60 percent support that pollsters prefer to see before an election.

Mayor Lee's position

Mayor Ed Lee supports a "significant" increase, but has not settled on what it should be, said spokeswoman Christine Falvey. He is working with a group of small-business owners, labor and community leaders on crafting a measure to put before voters in November.

Meanwhile, $15-an-hour advocates will huddle this week to discuss their next move in light of the poll results.

Likely standing in their way will be some small-business leaders and the Golden Gate Restaurant Association, who say that raising the minimum wage would cause collateral damage. They predict that businesses would raise prices and shed employees. And some would close.

A $15-an-hour mark "would have a huge impact" on the city's restaurants, said Gwyneth Borden, executive director of the Golden Gate Restaurant Association. "Restaurants would raise their prices. There's no other way to remediate out of it."

Plus, Borden said, when San Franciscans voted in 2003 on the minimum wage, they supported a 26 percent increase. Bumping it to $15 an hour now would be a 40 percent jump.

According to national economic research, a 10 percent increase in the minimum wage leads to price increases in restaurants of about 0.8 percent, said Michael Reich, a professor of economics and director of the Institute for Research on Labor and Employment at UC Berkeley.

But the city's last minimum wage bump didn't cause prices or the unemployment rate to spike.

Even though San Francisco has also mandated universal health care and paid sick leave in addition to its higher minimum wage, private-sector employment grew 5.6 percent from 2004-11, according to a recent study by UC Berkeley economists. Employers absorbed the higher wage costs largely through reduced turnover, lower absenteeism and fewer grievances. The study found a 2.8 percent increase in restaurant prices due to the minimum wage increase.

Meanwhile, advocates for low-income workers say boosting the minimum wage to $15 an hour would put an additional $8,861 annually in the hands of each full-time minimum wage worker in San Francisco.

Many need public aid

Now, many working people need public assistance. A national study by the UC Berkeley Labor Center in October found that 52 percent of the families of fast food workers are enrolled in one or more public assistance programs, compared with 25 percent of the workforce as a whole.

In California, researchers estimate that low-paid fast food workers cost taxpayers $717 million a year in state and federal assistance, according to the UC center's study, which was co-authored by researchers at the University of Illinois at Urbana-Champaign.